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The possibility of proficient use of heavy oil residues and oil refining wastes as carbon additives in coal charges for metallurgical coke production is investigated. Involvement of petroleum coke fines and coking additives in coal charges makes it possible to significantly improve the performance properties of blast furnace coke. The available and prospective caking additive production technologies using heavy oil residues are studied and compared. [ABSTRACT FROM AUTHOR]

Technological schemes of delayed coking plants currently operated in oil refineries are compared. It is shown that the new-generation Russian technology is superior to licensed technologies of foreign firms in operational reliability, efficiency, and potentiality of producing various types of coke. [ABSTRACT FROM AUTHOR]

The production of a highly anisotropic structure of needle cokes depends not only on the quality of the feedstock but also on the hydrodynamic situation in the coke chamber formed as a result of shear stresses in the mesophase matrix by flows of released vapor-gas products of the coking distillate and continuous delivery of the raw materials. This paper presents the results of investigations on the quality of needle cokes produced during coking under static and dynamic conditions. It was shown that the microstructural organization of cokes can differ quite significantly depending on the coking technology. [ABSTRACT FROM AUTHOR]

Abstract—The present paper is devoted to the study of the possibility of estimating the reproductive potentials of wild ungulate populations and, possibly, other large mammals, on the basis of the time series of their numbers. We have found out that this is possible, which is confirmed by the high quality of approximation of the time series of abundance by logistic curves and the corresponding coefficients of their determination for different species ranging from 75 to 96%. For such calculations, one circumstance is necessary—that the population of the studied species has been briefly exposed to some unfavorable factor causing a significant reduction in its numbers with subsequent restoration to the previous level, or that the time series contains a well-expressed and extended section of the transition of the population from some lower level to the upper level of the population, passing into a stationary state. The values of the maximum exponential growth rates of ungulate populations that we obtained do not fundamentally differ from the data available in other researchers' works. In addition, it should be borne in mind that our method for assessing the reproductive potentials of ungulates is statistical, with features accompanying all such methods, for example, the presence of statistical errors in all determined parameters. However, the evaluation of the magnitude of these errors is a topic for a separate study. [ABSTRACT FROM AUTHOR]

The paper presents data on the abundance of bobak marmot (Marmota bobak Müller, 1776), obtained from 1987 till 2019. All censuses were performed according to one technique developed by us in the late 1980s. During these long-term investigations, the structure of the bobak marmot areal in the Saratov region was studied. The dynamics of its numbers is described, and its trends for individual groups of districts were revealed, distinguished by trends, the time of the appearance of new settlements as a result of reintroduction after a prolonged depression in the numbers caused by both plowing of the steppes and the well-known events of the 1920s, 1930s and 1940s, when the bobak marmot provided the survival of some part of the population. It has been established that the population peak in the indigenous settlements that have been existing from the end of the Pleistocene–the beginning of the Holocene, was in 1980–1990. New settlements arise in the territories where the marmot was reintroduced, and the species abundance continues to grow. This, first of all, refers to the western slopes of the Volga Upland and the Oka-Don plain, formerly inhabited by marmots. An increase in the numbers of the Kazakhstan subspecies of the bobak is observed at the eastern end of the Syrt plain and on the spurs of the Common Syrt in the Saratov Trans-Volga region. The genetic studies of steppe marmots by R.V. Naumov (2019) on the right Volga bank of the Ulyanovsk region showed that a genetically homogeneous population lives on the vast territory of the Volga region. This casts doubt on the assumption of the existence of the Kozlovi subspecies of the bobak marmot in the local territories of the Voskresensk, Volsk and Khvalynsk districts of the Saratov region, which served as the ground for its inclusion into the new edition of the Red Data Book of the region, which we consider unreasonable (Resolution..., 2019). [ABSTRACT FROM AUTHOR]

The article presents the implementation of CFD/FEM approach for real oil tank of the gas turbine engine for the purposes of prediction of the component behavior under the local impact of a burner jet. The model takes into account heat and mass transfer problems as well as strength problems that are solved using a one way coupled fluid-structure interaction method. Results of the blind test simulation are compared and show good agreement with available experimental data. [ABSTRACT FROM AUTHOR]

Abstract: Advanced techniques for optical manipulation of nanoscale objects are presented. Possible mechanisms of enhancement of the effect of light on nanoobjects are listed. Enhancements by plasmon effects, field amplification in high-Q resonators, and collective effects are characterized. These methods are suitable for manipulation of various nanoobjects: quantum dots, nanowires, nanotubes, and cell organelles. Techniques for the measurement of forces at nanometer scales with atomic force microscopes are discussed. [ABSTRACT FROM AUTHOR]

Delayed carbonization is one of the most dynamically developing technologies in global petroleum processing. The basic factors determining the material balance and the quality of carbonization products are process parameters and quality of the feedstock used. However, data on the dependence of yield of gaseous and liquid carbonization products on the quality of the feedstock are absent in the domestic literature. This paper presents the developed mathematical models of the yield of heavy oil residue carbonization products, which help control products yield by varying the proportions of the components in the feedstock, taking account of the change in carbonizability of each component of the feedstock. [ABSTRACT FROM AUTHOR]

Radical reconstruction of a slow-coking plant, which makes it possible to increase productivity with respect to feedstock by a factor of 1.5, and shorten the coking cycle from 42–48 to 28 h while retaining the quality of the products obtained, is described. [ABSTRACT FROM AUTHOR]

The lithologic-genetic formation conditions of a reservoir of industrial groundwater on Siberian Platform, associated with the existence of a bank reef in the Cambrian. Within this cryohydrogeological structure, the properties and reserves of the hydromineral stock that can be developed parallel to the diamond-mining on Udachnaya pipe without significant environmental damage. [ABSTRACT FROM AUTHOR]

The structure of glasses of the compositions xEr2O3-2 xTiO2-(100-3 x )TeO2 was investigated and the glass formation region, situated in the range of 2 < x < 7 was established. The possibility of increasing the glass transition temperature and consequently the thermal stability of erbium tellurite glass by doping with titanium (IV) oxide was demonstrated. [ABSTRACT FROM AUTHOR]

Transparent glass composites containing nonlinear optical (NLO) and luminescent crystals are of significant interest for the optical materials science in spire of a lot of difficulties to synthesize high-quality NLO composites: refractive index and density matching! of glass matrix and crystal, controlled chemical interaction between them, absence of crystal aggregation, cords, bubbles, etc. Low density and refractive index, high second harmonic generation (SHG) activity, rather a high melting point allow to refer KNbSi2O7 ferroelectric to a promising candidate for using in the NLO glass composite technology. Manifestation of NLO properties of crystals in glass composites is established to depend drastically on glass matrix composition. During re-melting lead containing glasses react chemically with KNbSi2O7 forming pyrochlore Pb2Nb2O7 which is dissolved gradually up to nano-scaled state exhibiting moderate SHG efficiency by analogy with nanostructured glasses because of space modulation of polarizability originated from nano-sized inhomogeneities enriched with Pb and Nb. Using of TeO2-based glasses permits to match reft active indexes of glass matrix and crystal, reduce glass melting temperature and fabricate transparent composites containing micron and sub-micron crystals with high second harmonic generation activity. [ABSTRACT FROM AUTHOR]

The first nonlinear optic nanocomposite based on a low-melting vitreous matrix and a ferrielectric crystal has been obtained. The matrix consists of lead-borate glass and the filler is single-phase powder of ferrielectric KNbSi2O7. The quadratic optical nonlinearity of composites was studied depending on temperature and time of dissolution of crystals in the glass matrix. Conditions for producing transparent nanocomposites that generate the second optic harmonic are identified. [ABSTRACT FROM AUTHOR]

The optical response of a diatomic system excited by monochromatic light is studied. On the basis of a semiclassical approach, the effects of rearrangement of the energy spectrum of the system due to the dipole-dipole interaction and the effects related to variations in the orientation of the atomic dipole moments under the action of microscopic fields are jointly taken into account. The strongest response of the system is shown to occur at dimensional resonance frequencies. The number of observed intensity peaks depends on the position of the observation point with respect to the interatomic axis. The frequencies of the dimensional resonances are compared with other characteristic frequencies of the atomic spectrum. [ABSTRACT FROM AUTHOR]

The problem of classical optics related to the electromagnetic-field distribution near the surface of a dielectric medium with allowance made for its discrete structure is solved. The effect of a probe on the nearfield optical observations is taken into account, and the condition is obtained under which this effect can be neglected. It is shown that the near-field observations can be used to get information not only on the surface structure but also on the effective fields in the near-surface region. A method for optically controlling the probe position over the surface is proposed. [ABSTRACT FROM AUTHOR]

The microscopic theory of a transitional layer on the ideal surface of a semi-infinite absorbing or nonabsorbing isotropic dielectric is developed within the framework of classical optics when the polarization vector of the medium is a linear function of the electric field strength inside the medium. The concentration of atoms (molecules) of the medium and their polarizability are independent of coordinates and are constant inside the medium and close to its surface. The consideration is carried out within the framework of the concept of a discrete-continuous dielectric, in which the fields of dipoles of discretely distributed atoms (molecules) inside the Lorentz sphere surrounding the observation point are taken into account. The near-field effect is shown to result in a nonexponential behavior of the field nearby the surface. The thickness of the transitional layer can be found from experimental values of the reflected wave amplitude. [ABSTRACT FROM AUTHOR]

A boundary problem of linear classical optics is solved in which the behavior of the electromagnetic field near the surface of a dielectric medium is studied. It is shown that including the discrete structure of a medium into the analysis has the most substantial effect on the behavior of the electromagnetic field at distances smaller than 2a[sub 0], where a[sub 0] is the lattice constant. This fact makes it possible to obtain numerical estimates of the size of the region where the reflected and transmitted waves are formed. [ABSTRACT FROM AUTHOR]

A boundary-value problem of nonlinear resonance optics in the interaction of intense light with a superthin film of two-level atoms is solved. In solving this boundary-value problem, the authors draw on the idea of a discrete-continuous system in which the atoms are distributed in a discrete manner in the vicinity of the point of observation. It is shown that detailed account of the dipole field leads to a near-field effect both inside the film and outside it in the near zone with respect to outer film surfaces. Various properties of the near-field effect in stationary irradiation of the film with quasi-resonance radiation with allowance for a resonance shift are investigated. It is shown, in particular, that, in the near zone, there is a nonexponential dependence of the fields of reflected and transmitted waves on the coordinate of the point of observation. [ABSTRACT FROM AUTHOR]

A luminescent method has been developed for evaluating the thickness of thin transparent luminescent coatings on surfaces of solid bodies by means of an equipment consisting of instruments produced by our industry. The high sensitivity of photomultipliers and the high definition of their luminous beam (of the order of 1 μ) are suitable for measuring the surface of thin films either at separate points, or for plotting their thickness diagrams along a definite path of the tested surface. This method can be recommended for evaluating oil coatings over rough metal surfaces. The method used for this purpose to date has consisted of applying lubricating layers of volatile solvents, with their thickness being evaluated by computation from the concentration of the solution and the area which it covered. This method contributes considerable errors. First, it is assumed that an oil film of a definite thickness is thus produced, whereas even on a smooth surface the oil is distributed nonuniformly, and all the more so on a rough surface. Second, the true area of a rough surface is not known, and it is assumed in calculations that the surface is smooth. These errors can be reduced by using the luminescent method. The same technique can be used for evaluating the distribution of lubricants over a friction path, for testing the uniformity and continuity of certain decorative or insulating coatings, etc. Thus, the measurement of film thicknesses by the luminescent method can be used both in scientific research and in industry. [ABSTRACT FROM AUTHOR]

When direct vision is obstructed, detecting an object usually involves either using mirrors or actively controlling some of the properties of light used for illumination. In our paradigm, we show that a highly scattering wall can transfer certain statistical properties of light, which, in turn, can assist in detecting objects even in non-line-of-sight conditions. We experimentally demonstrate that the transformation of spatial coherence during the reflection of light from a diffusing wall can be used to retrieve geometric information about objects hidden around a corner and assess their location. This sensing approach is completely passive, assumes no control over the source of light, and relies solely on natural broadband illumination. Non-line-of-sight sensing requires purposely controlling some of the properties of light during the measurement process. Here, the authors show that reflection from a diffusive surface preserves some coherence properties and the shape and the distance to an incoherently illuminated object can be measured using the spatial coherence function. [ABSTRACT FROM AUTHOR]